/Engine/Plugins/Experimental/MeshModelingToolsetExp/Source/SkeletalMeshModifiers/Public/SkinWeightModifier.h
Set bone weights for a single vertex. The weights are stored as supplied and not normalized until either "CommitWeightsToSkeletalMesh()" or "NormalizeVertexWeights()" is called.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category="Weights") bool SetVertexWeights ( const int32 VertexID, const [TMap](API\Runtime\Core\Containers\TMap)< [FName](API\Runtime\Core\UObject\FName), float > & InWeights, const bool bReplaceAll )